Horizontal Section No. 61 (1861). 1.From the Erewash Valley Railway, nr Codnor Park, across the Derbyshire Coalfield, to S of Birmingham. 2.From E of Chesterfield, across the Coal Measures, to E of Ollerton. Geological Survey of GB. 1stHorizontal Section No. 61 (1861). 1. W to E from the Erewash Valley Railway, near Codnor Park, across the Derbyshire Coalfield, to Toot Hill, S of Birmingham. 2. From W to E ,from 2 miles E of Chesterfield, crossing the Coal Measures, to the windmill 3 miles E of Ollerton. Geological Survey of GB. 1st edition. Located on Old Series one inch maps 71nw and ne, 82sw and se. Hand coloured engraving, 69 x 103cm, 1: 10,560 scale (6= 1mile). Flat, linen